Thermal Profile Data Research Articles

Boosting Detection of Low-Abundance Proteins in Thermal Proteome Profiling Experiments by Addition of an Isobaric Trigger Channel to TMT Multiplexes.

The study of low-abundance proteins is a challenge to discovery-based proteomics. Mass spectrometry (MS) applications, such as thermal proteome profiling (TPP), face specific challenges in the detection of the whole proteome as a consequence of the use of nondenaturing extraction buffers. TPP is a powerful method for the study of protein thermal stability, but quantitative accuracy is highly dependent on consistent detection. Therefore, TPP can be limited in its amenability to study low-abundance proteins that tend to have stochastic or poor detection by MS. To address this challenge, we incorporated an affinity-purified protein complex sample at submolar concentrations as an isobaric trigger channel into a mutant TPP (mTPP) workflow to provide reproducible detection and quantitation of the low-abundance subunits of the cleavage and polyadenylation factor (CPF) complex. The inclusion of an isobaric protein complex trigger channel increased detection an average of 40× for previously detected subunits and facilitated detection of CPF subunits that were previously below the limit of detection. Importantly, these gains in CPF detection did not cause large changes in melt temperature (Tm) calculations for other unrelated proteins in the samples, with a high positive correlation between Tm estimates in samples with and without isobaric trigger channel addition. Overall, the incorporation of an affinity-purified protein complex as an isobaric trigger channel within a tandem mass tag (TMT) multiplex for mTPP experiments is an effective and reproducible way to gather thermal profiling data on proteins that are not readily detected using the original TPP or mTPP protocols.

Obtenção numérica do perfil térmico durante passagem de fonte de calor nos materiais AISI 410, 304L e 430

O método de elementos finitos é uma análise numérica capaz de responder diversos problemas transientes, não lineares da engenharia. O objetivo desse trabalho foi realizar uma pesquisa experimental de análise numérica via elementos finitos, em busca da resposta a um aporte térmico em três materiais inoxidáveis, sendo eles AISI 410, AISI 304L e AISI 430. Para isso foi utilizado o software Ansys® Academic 2020R1, nele foram modeladas chapas nas dimensões de , com um caminho de passagem da fonte de calor de . Os materiais foram criados com suas propriedades físicas transiente. A fonte de calor adotada foi a Gaussiana, retirada de uma extensão matemática própria para o software. Foram consideradas as perdas de calor por condução na peça, convecção e radiação no ambiente. A construção do perfil de temperatura de cada material foi construída de acordo com a temperatura máxima atingida, temperatura em pontos específicos e máximo fluxo de temperatura. Os dados dos perfis de temperatura dos materiais foram comparados utilizando por análise estatística ANOVA, utilizando o teste de Tukey. Os resultados mostraram a possibilidade de realizar simulação de processos de soldagem com as condições de contorno adotadas, mostraram que não há uma diferença de máxima temperatura entre os três materiais, entretanto existe uma diferença significativa entre os máximos fluxos de temperatura obtidos entre os três matérias, fato justificado pelas suas diferenças de propriedades físicas. Além disso, os dados de perfil térmico permitem análises estruturais dos materiais, bem como predições de caminhos a seguir em ajuste de parâmetros experimentais.

Tool steel and copper coatings by friction surfacing – A thermography study

Infrared thermography was used to record thermal profiles during friction surfacing. Thermal profiles for different sets of consumable rod/substrates (tool steel/steel; copper/steel and copper/copper) were recorded and analyzed. The thermal profiles showed distinct stages of plastic deformation with respect to temperature. The mechanism of bonding or no-bonding was discussed based on thermal profile data. It was found that a metallurgically bonded coating can be obtained if the flow stress of the plasticized material is comparable with the localized stress developed due to axial loading.

The effects of littoral zone vegetation on turbulent mixing in lakes

Micro-scale thermal profile data were acquired in four lakes in northwest England and southeast Australia that ranged from a small, sheltered pond with a surface area of about 1 ha to more open lakes with surface areas of several square kilometres. These lakes provided a range of topographic and climatic contexts, basin morphologies and dominant macrophyte species. The data were acquired using two SCAMP profilers, one deployed in the open water and the other mounted on a field traverse deployed within the vegetated littoral zone. From these profile data, turbulence parameters were calculated. The results show the variation in the influence of vegetation on turbulence in the four lakes, which depends on the combination of wind stress, solar radiative forcing and macrophyte mechanical properties. In the sheltered pond, the vegetation alters the light climate within the water, thus reducing stratification and allowing weak, thermally-driven mixing. In the larger lakes, however, the primary action of the vegetation is to prevent surface-generated TKE from penetrating the water column, although this effect becomes less important as the plant separation increases. A simple mechanistic model, calibrated against the field data, suggests that the macrophyte mechanical properties are most important in determining the turbulent kinetic energy (TKE) profile. Increasing the number of turbulence-generating plants reduces the transport of surface-generated TKE into the deeper water, consistent with the field observations. The model suggests that solar forcing, as measured by the temperature gradient between the surface and bottom waters, is of less importance since the TKE profile is similar in runs with different gradients. Perhaps most surprisingly, the value of the surface-wind stress used in the model is not important, within the limitations of the model, as it does not change the TKE profile, except in a thin surface layer.

MODELING AND OPTIMIZATION OF REFLOW THERMAL PROFILING OPERATION: A COMPARATIVE STUDY

ABSTRACT In this study, a comparative study of optimizing the reflow thermal profiling parameters using a hybrid artificial intelligence and the desirability function approaches without/with combining multiple performance characteristics into a single desirability is presented. Reflow soldering is the key determinant for the improvement of the first-pass yields of electronics assembly. A reflow thermal profile is a time-temperature contour with multiple performance characteristics utilized to monitor the heating effects on a printed circuit board (PCB) and surface mount components (SMCs) in the reflow oven. The use of an inadequate reflow thermal profile may not only produce a variety of soldering failures, but can also result in the needs for considerable reworking and waste. An L18 (21*37) Taguchi experiment design is conducted to collect the thermal profiling data. A quick propagation (QP) neural network is modeled based on experimental data to formulate the nonlinear relationship between the thermal profiling factors and responses, and a genetic algorithm (GA) is used in the optimization of thermal profiling factors with the fitness function based on the trained QP neural network model. Alternatively, the response columns for the experimental data can be transformed into a single measure of desirability which is then optimized by the desirability function approach with the response weightings derived from an analytic hierarchy process (AHP). The empirical evaluation results show that the desirability function approach with combining the multiple performance into a single desirability delivery superior soldering performance to that obtained by the hybrid artificial intelligence method without combining the multiple performance into a single desirability, as measured by the DPMO, yield rate, and process sigma.

Green roofs are not created equal: the hydrologic and thermal performance of six different extensive green roofs and reflective and non-reflective roofs in a sub-tropical climate

Green roofs have the potential to retain stormwater on the roof surface and lower the thermal loading on buildings. Because of this, the greatest environmental benefits from green roofs might be achieved in subtropical climates characterized by high temperatures and intense rain events. There is, however, little research to support this. In a replicated study in Texas, we compared the performance of six different extensive green roof designs vegetated with native species, to non-reflective (black) roofs, and reflective (white) roofs. Preliminary hydrologic and thermal profile data indicated not only differences between green and non-vegetated roofs, but also among green roof designs. Maximum green roof temperatures were cooler than conventional roofs by 38°C at the roof membrane and 18°C inside air temperature, with little variation among green roofs. Maximum run-off retention was 88% and 44% for medium and large rain events but some green roof types showed very limited retention characteristics. These data demonstrate indicate that: 1. Green roofs can greatly affect the roof temperature profile—cooling surface layers and internal space on warm days. 2. Green roofs can retain significant amounts of rainfall, this is dependent on the size of the rain event and design and can fail if not designed correctly. We suggest that as green roofs vary so much in their design and performance, they must be designed according to specific goals rather than relying on assumed intrinsic attributes.

Thermal profiling for parallel on-line monitoring of biomass growth in miniature stirred bioreactors

Recently we have described the design and operation of a miniature bioreactor system in which 4-16 fermentations can be performed (Gill et al., Biochem Eng J 39:164-176, 2008). Here we report on the use of thermal profiling techniques for parallel on-line monitoring of cell growth in these bioreactors based on the natural heat generated by microbial culture. Results show that the integrated heat profile during E. coli TOP10 pQR239 fermentations followed the same pattern as off-line optical density (OD) measurements. The maximum specific growth rates calculated from off-line OD and on-line thermal profiling data were in good agreement, at 0.66+/-0.04 and 0.69+/-0.05 h(-1) respectively. The combination of a parallel miniature bioreactor system with a non-invasive on-line technique for estimation of culture kinetic parameters provides a valuable approach for the rapid optimisation of microbial fermentation processes.

PHYSICAL PROPERTIES OBTAINED FROM MEASURED THERMAL PROFILES IN THE FILM/SUBSTRATE BIMATERIAL SYSTEM

The microelectronic devices are formed by a substrate that supports the functional thin film material. The thermal, electrical, and mechanical properties of the system depend strongly on the interfacial properties between a film and a substrate. The interfacial nature in a film/substrate system originates the thermal contact resistance (R tc ). We discuss the thermal and the electrical behavior in a film/substrate system (bimaterial system) making emphasis on the R tc of the interface. Au /glass samples with different thicknesses were prepared by thermal evaporation for experimentation. The bimaterial system was heated by a DC electrical current to obtain thermal profiles. Film and substrate thermal profiles acquired with high resolution combined with a developed bimaterial model are used as an alternative method to estimate the R tc value at atmospheric pressure, the electrical resistivity ρ, and the thermal resistive coefficient α r in the bimaterial system. The calculated R tc values ranged from 7.7 × 10-4 to 1.2 × 10-3 m2 K/W for the Au /glass system, in good agreement with previously reported values. The ρ values obtained from the thermal profile data present a more reliable value due to the global character than the local values measured by the four-probe technique. Dependence on film thickness was also found in the α r coefficient determination.

Multiscale Characterization of a Heterogeneous Aquifer Using an ASR Operation

Heterogeneity in the physical properties of an aquifer can significantly affect the viability of aquifer storage and recovery (ASR) by reducing the recoverable proportion of low-salinity water where the ambient ground water is brackish or saline. This study investigated the relationship between knowledge of heterogeneity and predictions of solute transport and recovery efficiency by combining permeability and ASR-based tracer testing with modeling. Multiscale permeability testing of a sandy limestone aquifer at an ASR trial site showed that small-scale core data give lower-bound estimates of aquifer hydraulic conductivity (K), intermediate-scale downhole flowmeter data offer valuable information on variations in K with depth, and large-scale pumping test data provide an integrated measure of the effective K that is useful to constrain ground water models. Chloride breakthrough and thermal profiling data measured during two cycles of ASR showed that the movement of injected water is predominantly within two stratigraphic layers identified from the flowmeter data. The behavior of the injectant was reasonably well simulated with a four-layer numerical model that required minimal calibration. Verification in the second cycle achieved acceptable results given the model's simplicity. Without accounting for the aquifer's layered structure, high precision could be achieved on either piezometer breakthrough or recovered water quality, but not both. This study demonstrates the merit of an integrated approach to characterizing aquifers targeted for ASR.

In-situ infrared thermographic analysis during dehydrogenationof cyclohexane over carbon-supported Pt catalysts using spray-pulsed reactor

Infrared thermography, a tool used for screening of active catalytic materials generally during the exothermic reactions has been used for thermal imaging during strong endothermic reaction of dehydrogenation of cyclohexane on Pt catalyst supported on active carbon cloth (CFF-1500s) sheets. A spray-pulsed mode was used for injection of atomized cyclohexane and to create alternate wet and dry condition on catalyst surface. The simultaneous product gas analysis and recording of the temperature profile of the catalyst surface using an IR camera was carried out. The production rate of hydrogen via endothermic dehydrogenation reaction is greatly dependent on the temperature of the catalyst surface. The observed change in the temperature profile at wet and dry conditions with varying pulse-injection frequency and corresponding product gas analysis reveals that the spray-pulse mode is useful in improving the catalyst activity. Further the reaction conditions were optimized using thermal profile data.

Assessment of wind‐stress errors using bias corrected ocean data assimilation

AbstractCurrent seasonal forecasting methods make extensive use of wind‐stress products and ocean thermal profile observations to produce ocean analyses for retrospective forecasts. The combination of inaccurate wind‐stress forcing and relatively accurate ocean thermal profile observations can have significant detrimental impacts on the analysis in equatorial regions as it leads to an imbalance between the zonal pressure gradient and wind stress. Model integrations have been performed to assess various wind‐stress products using a Pacific region ocean general‐circulation model in three assimilation modes. The assimilation of thermal profile data has been shown to impact negatively on the zonal and vertical current structure. A bias correction scheme has been used to illustrate how these errors can be mitigated. The method used to correct for these systematic errors allows for the errors to evolve in time and space. The strength of the equatorial undercurrent is brought to a realistic level, but the scheme does reduce its variability. The European Remote Sensing satellite scatterometer wind products have been used to illustrate the methodology and comparisons have been drawn with several other wind‐stress products. © Royal Meteorological Society, 2004. Contributions by M. R. Huddleston, M. J. Bell and M. J. Martin are Crown copyright.

The effect of Keepit Dam on the temperature regime of the Namoi River, Australia

AbstractModifications to water temperature caused by the release of hypolimnetic water from thermally stratified reservoirs pose a major threat to the aquatic biota of lowland rivers in Australia's Murray–Darling basin. Keepit Dam is earmarked as one of several deep‐release structures in the basin causing ecologically significant temperature modification over a large length of river. This study utilized discrete and continuously monitored historical water temperature data from stream gauging stations, together with reservoir thermal profile data, to assess the impacts of Keepit Dam on the thermal regime of the Namoi River. Modifications to selected components of the river's annual temperature cycle were quantified in relation to a pre‐dam temperature regime estimated from statistical models incorporating catchment, hydrological and sample attributes. Keepit Dam has modified the thermal regime of the Namoi River. The effect was greatest immediately downstream from the dam where the annual maximum daily temperature was approximately 5.0 °C lower and occurred three weeks later than the pre‐dam condition. This change was sufficient to disrupt thermal spawning cues for selected Australian native fish species. The magnitude of disturbance progressively diminished with distance from the dam. Key aspects of the river's annual temperature cycle were largely restored to the pre‐dam condition within 100 river km downstream from the dam, which is closer than previous estimates. However, there was marked inter‐annual variation in the magnitude of thermal modification and ecological impact as a result of year to year changes in tributary flow and reservoir behaviour. Copyright © 2002 John Wiley & Sons, Ltd.

Microstructural features induced by spray forming of a ternary Pb-Sn-Sb alloy

An alloy containing Pb-12% Sn-12% Sb with small addition of copper and arsenic was spray deposited employing two different atomization gas pressure and nozzle to substrate distances. The temperature of the spray-deposit was measured during deposition at a distance of 2 and 10 mm above the substrate-deposit interface. Thermal profile data indicated small variation in temperature with time during deposition stage whereas during post deposition stage an exponential decrease in temperature was recorded. Second phase particle size along the thickness of the deposit varied from 4 to 8 μm compared to 70 to 80 μm size of these particles in the as cast alloy. Maximum porosity occurred in the section of the deposit near the contact surface of the substrate and also in its peripheral regions. X-ray diffraction analysis exhibited the formation of additional Cu2Sb phase in the spray-deposit and CuSn and Cu3.3Sb phases in atomized powders compared to that of the as cast alloy. The microstructural evolution during spray deposition of this alloy is discussed.